Their sweet burn is what makes us all swoon — quite literally — for the sauce.

The peppers used in Sriracha contain two molecules in the capsaicin family that trigger the production of a special protein in our mouths. That protein, called TRPV1, is designed to respond to hotter-than-boiling temperatures by triggering the release of pain-killing molecules called endorphins — the same feel-good chemicals that get released when we exercise, eat chocolate, or have sex.

According to the scoville scale, which ranks spicy foods based on how much they would need to be diluted by a solution of water and sugar to make their heat undetectable, Sriracha is somewhere in the mild-to-medium range. With a scoville ranking of 1,000 to 2,500 (depending on the patch of peppers your bottle came from), Sriracha ranks slightly more timid than Tabasco, which has a ranking of 2,500 to 5,000 scoville.

A pure habanero pepper, by comparison, clocks in at 350,000. Two of the world's hottest peppers rank far higher — the aptly named Trinidad Moruga Scorpion and Carolina Reaper rank somewhere between 1.5 million and 2 million scoville.